Allan M. Strong
Male Bobolink from a field enrolled in the project in 2014 (All photographs by Allan M. Strong)
As humans have altered land use patterns in New England, some species of birds are winners and other are losers. When you look at these changes over long time periods, some groups of species, such as grassland birds, have had it both ways. When Europeans colonized the Northeast, they transformed a landscape that was nearly 100% forested to one that by 1800 was 70% pasture and cultivated land. At the end of the Civil War, that trend started to reverse; now, roughly 67% of the Northeast is forested. As a result of these land use changes, we’ve seen the populations of grassland birds go from local rarities to common, widespread species, and then back to local rarities (see Table 1 below).
Although it is easy to correlate changes in the populations of grassland birds to changes in land use patterns, the issue is not quite that simple. The distinction between farmland and forest is straightforward, but the quality of farmland for grassland birds can vary dramatically depending on the crop and management practices. For the species of grassland birds that nest in the Northeast, most avoid row crops. Corn and soybeans in particular provide low quality habitat for these species. By contrast, forage crops, either grasses or legume-grass mixtures, can provide high quality habitat for grassland birds. Although there is some variation in habitat quality with respect to the particular species that are planted, for the most part it is the management practices, namely the frequency and timing of cutting and grazing, that have had the greatest effect on the reproductive success of grassland birds.
In 2002, my colleagues Noah Perlut, Therese Donovan, Neil Buckley, and I started a project to look at the effects of agricultural management on the reproductive ecology of grassland birds in the Champlain Valley of Vermont and New York. The project was funded by the US Department of Agriculture’s Managed Ecosystems program. Although we were interested in developing management practices that would increase the probability of successful nesting, we also wanted to develop these practices within the context of maintaining a viable agriculture industry in the Champlain Valley. We were keenly aware that the reason why grassland birds continue to live in this area is because of the agricultural industry, primarily dairy-dominated, in this part of the Northeast. We wanted to develop management practices that would enable farmers to be successful economically while still providing high quality habitat for grassland birds.
|
State |
Species |
MA |
NH |
ME |
VT |
NY |
Northern Harrier |
T |
E |
SC |
SC |
T |
Upland Sandpiper |
E |
E |
T |
E |
T |
Short-eared Owl |
E |
|
T |
|
E |
American Kestrel |
|
SC |
|
SC |
|
Loggerhead Shrike |
|
|
SC |
E |
E |
Horned Lark |
|
SC |
SC |
|
SC |
Sedge Wren |
E |
E |
E |
E |
T |
Vesper Sparrow |
T |
SC |
|
SC |
SC |
Grasshopper Sparrow |
T |
T |
E |
T |
SC |
Henslow's Sparrow |
E |
|
|
E |
T |
Bobolink |
|
|
|
SC |
|
Eastern Meadowlark |
|
SC |
SC |
SC |
|
Table 1. Status of grassland birds in the northeastern United States.
E = Endangered, T = Threatened, and SC = Special Concern.
Because many species of grassland birds are so rare locally, we focused our field research on the two most common species in the region: Savannah Sparrows and Bobolinks. Based on previous research conducted via point counts, we found that these species made up approximately 93% of all grassland birds in our study area. Although we would love to know more about the ecology of other species, they are too rare to allow for collection of sufficient data.
Our approach to field research is relatively simple. We use mist nets to catch as many of the breeding adults as we can early in the breeding season. We mark them with a unique combination of colored leg bands so that we can identify them without having to recapture them. We follow these birds around our study sites and find as many nests as we can, with the goal of finding all nests of both species. When we find nests, we monitor them until the young fledge or the nest fails.
When we started our research, we worked in fields that were managed in four different ways, or treatments. Three treatments were simply variation in the timing of cutting. In the first treatment, fields were cut around Memorial Day weekend and then cut two or three times over the course of the growing season at roughly five-week intervals. This is essentially the pattern that most dairy farmers in the Champlain Valley follow, maximizing the protein content of the forage, which leads to greater milk production. The second treatment was a cut between the third week of June and the tenth of July. This cutting pattern is used by farmers who don’t need a high protein content in their forage, such as forage for beef cows, dry cows, and heifers. The last cutting treatment was one in which all cutting was delayed until the first of August. Rarely used by farmers, this treatment is common on land owned by hobby farmers who like to keep their land open, but may not necessarily have a need for their forage. Finally, we also set up plots in rotationally grazed pastures.
The results from this work were relatively clear. We found a nicely defined gradient of habitat quality, with Bobolinks fledging basically zero young/female in early cut fields, 1.5 young/female in fields that were rotationally grazed, 2.2 young/ female in fields cut in late June/July, and 2.8 young/female in fields cut in August. The pattern was similar for Savannah Sparrows. Neither species was immune to cutting.Essentially 100% of nests fail following hay harvest—either from nest destruction during the act of cutting or baling, or through depredation of exposed nests in the 1–2 days following the cut. If you are managing for grassland birds, the best management option is obvious. However, cutting fields in August produces low quality forage, which radically decreases milk production. Thus, for a dairy farmer, managing for grassland birds isn’t an economically viable alternative.
With every field project, there are always some surprises, and sometimes these surprises can yield the most interesting results. Although individual Savannah Sparrows and Bobolinks responded similarly to management practices with respect to reproductive output, the populations responded quite differently to cutting. After cutting, Savannah Sparrows stayed on the field and often renested within just a few meters of their original nest site, sometimes within 48 hours of a cut. By contrast, Bobolinks left the field and renested elsewhere. The Bobolinks that came back to a field to nest were different individuals than those that had attempted to nest in that field before the cut. This led to our development of an alternative management practice that had the potential to increase the reproductive success of grassland birds as well as provide economic benefits for landowners.
We partnered with the Vermont state office of the Natural Resources Conservation Service (NRCS) to create an incentive program, within a Farm Bill program called the Environmental Quality Incentives Program. This new program offered payments for farmers to delay their second cut for roughly 30 days (65 days after the first cut) to provide a sufficiently long window for birds to nest successfully. The program paid landowners $135/acre for a minimum of 20 acres, parcels that were approximately square in shape and were limited in the amount of reed canary grass on the site, which generally provides low quality nesting cover. The first cut, and all subsequent management activities, had to be completed by May 31, which we had found significantly increased the probability that Bobolinks would colonize the field to nest.
Nest from a field enrolled in the project in 2014. Five eggs is generally a full clutch.
We tested the program for three years and found that there was no difference in reproductive output for Bobolinks on fields in the delayed second cut program relative to fields cut for the first time in August. Because Bobolinks only rarely have a second brood, the primary cost was loss of their first nest. We were really excited about the program and within three years had enrolled nearly 1000 acres in Vermont.
Unfortunately, NRCS made a decision to evaluate the payment for the practice on a regional pricing scheme, and this analysis led to a decrease in the payment to landowners to less than $90/acre. As soon as the change in the payment was made, no additional landowners signed up for the program. This change led us to once again reevaluate our options for involving landowners in bird-friendly management practices. This time, we took a page from the books of ecological economics, where research has shown that the ecosystem services, i.e., goods and services provided by natural processes such as carbon storage, water filtration, pollination, and nutrient cycling are often provided at a significantly reduced cost relative to their man-made counterparts, e.g., tree planting, water treatment plants, apiculture, and landfills. We asked the question, would the public be willing to pay landowners directly for providing Bobolink habitat, even though it is still relatively easy to drive down a country road and see Bobolinks giving their emphatic, bubbling, flight song over a hayfield?
I teamed up with Stephen Swallow at the University of Connecticut and Lisa Chase at University of Vermont Extension on a grant from the US Department of Agriculture’s National Initiative for Food and Agriculture to set up The Bobolink Project in Vermont. The idea was simple. Landowners with suitable habitat submitted a bid for the lowest price that they would be willing to take to incorporate bird-friendly management on their property. We gave landowners the option of a delayed second cut or to wait until August 1 to cut their fields.
While collecting bids from landowners, we started a marketing campaign that asked people to pledge support to landowners. We asked the people who value grassland birds and their habitat to pay landowners directly to help them incorporate these declining species into their management activities. Although there are options for financial support for landowners from the federal government, we learned that these programs are inconsistent and may not provide long-term support to farmers. We were interested specifically whether people would be willing to give more money if their dollars could support greater acreages of bird-friendly management. Although this is a slightly different tactic than going to a website and pledging $50 for a worthy cause, we hoped that our ability to collect more money would lead directly to more Bobolinks fledged. Once the campaign closed in mid-April, we evaluated the money that we raised in relation to the bids collected from landowners. We used a reverse auction and ranked the bids from low to high, accepting sequentially higher bids until we could no longer pay landowners their asking price. This payment method provides an efficient allocation of the money we raise so that we are paying landowners exactly what they require to implement bird-friendly management practices.
Nest from a field that was enrolled in the project in 2014. The young are about 5 days old
In 2013, The Bobolink Project raised about $32,000, which led to payments to seven landowners for bird-friendly management on 200 acres. The math works out to $160/acre, which was significantly more than NRCS was paying two years earlier for the delayed second-cut program. In 2014, we raised about the same amount, but because word had spread about the project, we had much greater farmer interest, and the price came down to under $100/acre. We were able to support bird-friendly management on 340 acres. We had bids from farmers to include over 1500 additional acres in the project, which gives an indication of the growing interest in Bobolink conservation as well as the “payment for ecosystem services” model. We made conservative counts of all the nesting birds on the fields by walking transects through the entire 340 acres; we counted 157 males and 128 females. Bobolinks are notoriously difficult to census in this manner, but given our research on nesting success, we feel confident that we raised more than 200 Bobolinks in 2014.
The question is, where do we go from here? The Bobolink Project has been successful in large part because it is supported by a grant. As a result, every dollar that is donated is tax deductible and goes directly to landowners, meaning no overhead for the project. However, without grant funding, this approach is probably not sustainable in the long term without someone who is head-over-heels in love with Bobolinks. Federal incentive programs are also supported by tax dollars, but they can also be unreliable and are perhaps unsustainable.
For 2015, we’ve got just enough money left in the grant to run the project for one more season. In the meantime, the NRCS has gone back to a statewide formula to provide payments for delayed second cuts, now at $137/acre. This is great news for us, because we are seeing a dichotomy in bid prices offered by different types of landowners. Dairy farmers, who need high quality forage for their livelihood can only reduce their price per acre so low, regardless of how enamored they are of Bobolinks. By contrast, landowners who don’t need their hay for their livestock, or perhaps for just a few horses, have the ability to drastically reduce their bids to remain competitive. Thus, the higher price offered by NRCS for delayed second cuts may provide a way to level the playing field. Dairy farmers that have the ability to get onto their fields early and harvest their first cut in late May can enroll in the NRCS program. Landowners who don’t need the early first cut can submit a bid to The Bobolink Project and, if successful, cut their hay at the end of the breeding season.
One of the lessons learned through our work with hundreds of landowners is that everyone has a different relationship with the land. Those of us who are interested in bird conservation probably fantasize about having a couple hundred acres that we could manage for rare and endangered species. But we often forget about the tax burden, ;the time commitment, and the need to plan for the future of the land after our passing. These issues create real pressures, whether they are philosophical, psychological, or economic. Consequently, having a broad menu of conservation options available to landowners provides the best chance of success.
Grassland birds are a suite of species that are more reliant on private land than many of their forest dwelling relatives. As such, their conservation depends on working with private landowners, often one parcel at a time. By giving these folks a variety of opportunities to improve the quality of their habitat, we increase the likelihood that we’ll continue to support our declining grassland birds in the Northeast. For more information please visit The Bobolink Project.
Allan Strong is an Associate Professor and the Associate Dean in the Rubenstein School of Environment and Natural Resources at the University of Vermont. His research focuses on the factors that affect habitat quality for birds. He has investigated post-fledging dispersal of White-crowned Pigeons in Florida, the mating system of Bicknell’s Thrush in Vermont’s Green Mountains, and the wintering ecology of Ovenbirds and Swainson’s Warblers in Jamaica. Since 2002, much of his research has focused on the conservation and ecology of grassland birds in the Champlain Valley.